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    Apoptosis, autophagy & endoplasmic reticulum stress in diabetes mellitus
    (Wolters Kluwer Medknow Publications, 2016) Demirtas, Levent; Guclu, Aydin; Erdur, Fatih Mehmet; Akbas, Emin Murat; Ozcicek, Adalet; Onk, Didem; Turkmen, Kultigin
    The prevalence of diabetes mellitus (DM) is increasing secondary to increased consumption of food and decreased physical activity worldwide. Hyperglycaemia, insulin resistance and hypertrophy of pancreatic beta cells occur in the early phase of diabetes. However, with the progression of diabetes, dysfunction and loss of beta cells occur in both types 1 and 2 DM. Programmed cell death also named apoptosis is found to be associated with diabetes, and apoptosis of beta cells might be the main mechanism of relative insulin deficiency in DM. Autophagic cell death and apoptosis are not entirely distinct programmed cell death mechanisms and share many of the regulator proteins. These processes can occur in both physiologic and pathologic conditions including DM. Besides these two important pathways, endoplasmic reticulum (ER) also acts as a cell sensor to monitor and maintain cellular homeostasis. ER stress has been found to be associated with autophagy and apoptosis. This review was aimed to describe the interactions between apoptosis, autophagy and ER stress pathways in DM.
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    Comparison of TIVA and Desflurane Added to a Subanaesthetic Dose of Propofol in Patients Undergoing Coronary Artery Bypass Surgery: Evaluation of Haemodynamic and Stress Hormone Changes
    (Hindawi Ltd, 2016) Onk, Didem; Ayazoglu, Tulin Akarsu; Onk, Oruc Alper; Aksut, Mehmet; Gunay, Murat; Turkmen, Kultigin; Ozensoy, Aynur
    Introduction. Increased levels of stress hormones are associated with mortality in patients undergoing coronary artery bypass grafting (CABG). Aim. To compare total intravenous anaesthesia (TIVA) and desflurane added to a subanaesthetic dose of propofol. Material and Methods. Fifty patients were enrolled in this study. Fentanyl (3-5mcg/kg/h) was started in both groups. Patients were divided into two groups. The PD group (n = 25) received 1 minimum alveolar concentration (MAC) desflurane anaesthesia in addition to propofol infusion (2-3 mg/kg/h), while P group (n = 25) received propofol infusion (5-6 mg/kg/h) only. Biochemical data, cortisol, and insulin levels were measured preoperatively (T0), after initiation of CPB but before cross-clamping the aorta (T1), after removal of the cross-clamp (T2), and at the 24th postoperative hour (T3). Results. Systolic, diastolic, and mean arterial pressure levels were significantly higher in PD group than those in P group in T1 and T2 measurements (p <= 0.05). CK-MB showed a significant decrease in group P (p <= 0.05). When we compared both groups, cortisol levels were significantly higher in PD group than P group (p <= 0.05). Conclusion. Stress and haemodynamic responses were better controlled using TIVA than desflurane inhalation added to a subanaesthetic dose of propofol in patients undergoing CABG.
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    Melatonin Attenuates Contrast-Induced Nephropathy in Diabetic Rats: The Role of Interleukin-33 and Oxidative Stress
    (Hindawi Ltd, 2016) Onk, Didem; Onk, Oruc Alper; Turkmen, Kultigin; Erol, Huseyin Serkan; Ayazoglu, Tulin Akarsu; Keles, Osman Nuri; Halici, Mesut
    Background. Inflammation and oxidative stress (OxS) contribute to the pathogenesis of diabetic kidney disease (DKD) and contrastinduced nephropathy (CIN). Patients with DKD were found to be more prone to CIN. Interleukin-33 (IL-33) is a proinflammatory cytokine, but its role in DKDand CINis unknown. Methods. Thirty male Sprague-Dawley rats were enrolled. The first group was comprised of healthy rats (HRs), whereas the other four groups were made up of diabetic rats (DRs), diabetic rats with contrastinduced nephropathy (CIN + DRs), melatonin-treated diabetic rats (MTDRs), andmelatonin-treated CIN + DRs (MTCIN + DRs). All groups except the HRs received 50mg/kg/day streptozotocin (STZ). CIN + DRs were constituted by administrating 1.5mg/kg of intravenous radiocontrast dye on the 35th day. MTDRs andMTCIN + DRs were given 20mg/kg/day of intraperitoneal injection of melatonin (MT) from the 28th day for the constitutive seven days. Results. We observed increased IL-33 in the kidney tissue following induction of CIN in DRs. To determine whether MT is effective in preventing CIN, we administered MT in CIN + DRs and demonstrated that kidney tissue levels of OxS markers, inflammatory cytokines, and IL-33 were significantly diminished in MTCIN + DRs compared with other groups without MT treatment (p < 0.05). Conclusion. Inhibition of IL-33 with MT provides therapeutic potential in DKD with CIN.
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    Risk Factors for Acute Kidney Injury after Coronary Artery Bypass Surgery and Its Detection Using Neutrophil Gelatinase-Associated Lipocalin
    (Karger, 2016) Onk, Oruc Alper; Onk, Didem; Ozcelik, Fatih; Gunay, Murat; Turkmen, Kultigin
    Introduction: Acute kidney injury (AKI) is an important complication of cardiac surgery due to its high mortality. The aim of the present study was to detect the factors leading to AKI in patients who underwent coronary artery bypass surgery (CABS) and also to determine the optimal timing for detecting AKI using the biomarker neutrophil gelatinase-associated lipocalin (NGAL). Materials and Methods: The records of 375 patients who underwent CABS were reviewed in this case-control study. Ejection fraction (EF), common carotid artery intima-media thickness (CCA-IMT) and cross-clamp (C-C) time of the patients were recorded. Blood samples were taken from all patients on preoperative day 1 as well as 6, 12, 24, 36, 48 h and 7 days after operation. Biochemical parameters were studied in patients with and without AKI. Results: According to the Risk Injury Failure Loss End Stage criteria, 24 patients had renal risk, 17 had injury and 4 had failure. Postoperative 24-hour serum creatinine levels indicated the risk of renal dysfunction for only 4 patients in the AKI group. CCA-IMT, C-C time, haematocrit (HCT) and preoperative interleukin-6 levels were significantly higher in the AKI group than in the non-AKI group. Postoperative 6- and 12-hour NGAL levels in the AKI group correlated with postoperative 36-hour serum creatinine levels. The optimal cut-off values for postoperative 6- and 12-hour NGAL test were 310 and 283 ng/ml, respectively. The area under the curve was higher in the 12-hour NGAL test (p < 0.0086). Conclusion: The number of stenotic coronary arteries, EF, CCA-IMT and HCT are all important risk factors. Early postoperative NGAL results were highly specific for the early recognition of AKI. (C) 2016 S Karger AG, Basel